Compounds for improved stem cell differentiation into hepatocytes

ABSTRACT

The invention relates to the compounds of formula I and pharmaceutically acceptable salts and esters thereof, wherein R 1 -R 11  are as defined in the description and claims. In addition, the present invention relates to methods of manufacturing and using the compounds of formula I as well as pharmaceutical compositions containing such compounds. The compounds of formula I are useful in differentiating stem cells into more mature or adult-like hepatocytes for use as drug screening platforms and in disease modeling applications.

This application is a continuation of U.S. application Ser. No. 14/205,893, filed Mar. 12, 2014, now pending; which claims the benefit of U.S. Provisional Application No. 61/811,155, filed May 22, 2013 and U.S. Provisional Application No. 61/792,019, filed Mar. 15, 2013. The entire contents of the above-identified applications are hereby incorporated by reference.

The present invention relates to compounds, their manufacture, and pharmaceutical compositions containing them for differentiating stem cells into more adult-like hepatocytes.

During drug discovery and development there is a tremendous need for robust in vitro methods for modeling liver function. Current methods employing primary human hepatocyte cultures have well-documented shortcomings, namely donor to donor variability and functional instability. Similarly, hepatoma cell lines exhibit functional insufficiency and suffer from confounding genetic abnormalities inherent in tumor cell lines.

Although pluripotent stem cell derived tissues hold promise to address the problem of donor to donor variability, thus far most reports examining human induced pluripotent stem cell (hiPSC)-derived hepatocytes indicate that they are more similar in certain functions to fetal tissues than adult, which could make their extrapolation to the adult in vivo situation difficult. Thus, there is a need for better methods of differentiating pluripotent stem cells into more mature or adult-like hepatocytes to generate more relevant models for drug discovery, efficacy, and safety testing.

Successful differentiation of hIPSC into adult-like hepatocytes will facilitate drug discovery efforts for treatment of chronic liver diseases such as hepatitis B virus (HBV) infection. Chronic HBV (CHB) infection is a huge unmet medical need affecting ˜350 million people worldwide. Current treatments—nucleos(t)ide inhibitors and interferon (IFN)—are ineffective to clear the virus and are associated with viral resistance and/or adverse side effects. Based on the sequence variability of its viral genome, HBV is classified within 7 genotypes (genotype A-H; A-D being the major genotypes). The disease outcome of HBV infection are age- and genotype-dependent. Thus, most CHB infection results from vertical (mother-to-infant) transmission and/or infection during childhood. In contrast, ˜90% of adults exposed to the virus were able to clear HBV infection within 6 months. In addition, various clinical data have shown that viral genotypes influence HBV disease progression and response to IFN treatment. HBV is also known to evade host immune responses by various mechanisms including down-regulation of interferon-stimulated genes (ISGs). A better understanding of the complex interplay between HBV and host innate immunity may lead to new host/viral targets for treatment of CHB infection. However, efforts to discover novel, more efficacious antivirals for HBV have been hampered by the lack of physiological and robust in vitro systems. Current hepatoma-based systems, used both as producer- and target-cells, are neither robust nor capture the genotype diversity of HBV. Thus, new in vitro systems that are more physiologically relevant and support robust infection of all major HBV genotypes, preferably from clinical isolates, will be highly desirable. Such systems will not only be beneficial as drug screening platforms, but also for HBV disease modeling including assessment of genotype-dependent of interferon response.

Thus, there is a need for improved differentiation of stem cell-derived hepatocytes into more mature hepatocytes to support robust infection of patient-derived HBV from various genotypes for use as drug screening platforms and disease modeling.

The invention is concerned with the compounds of formula I:

and pharmaceutically acceptable salts and esters thereof, wherein R¹-R¹¹ are as defined hereinafter. In addition, the present invention relates to methods of manufacturing and using the compounds of formula I as well as pharmaceutical compositions containing such compounds.

The compounds of formula I are useful in differentiating stem cells into more mature or adult-like hepatocytes for use as drug screening platforms and in disease modeling platforms.

FIG. 1 provides a heat map showing the global increased expression of genes spanning hepatocyte function at multiple doses using the compound of example 1. Biology heat maps are typically used in molecular biology to represent the level of expression of many genes across a number of comparable samples (e.g. cells in different states, samples from different patients) as they are obtained from cDNA samples. ‘Green’ indicates low expression whereas ‘Red’ indicates high expression in FIG. 1. The graphical representation is relative across each row of data creating a gradient from lowest expression(green) to median(black) to highest expression(red).

FIG. 2 shows the increased expression of genes spanning hepatocyte function in induced pluripotent stem cell derived hepatocytes based on gene expression of a panel of maturation-associated genes after treatment with the compounds of examples 1-7.

FIGS. 3 and 4 show a robust HBV infection in iCell hepatocytes. FIG. 3 is a bar graph showing that treatment of induced pluripotent stem cell derived hepatocytes with the compound of example 1 led to cell susceptibility to HBV infection that occurred in a dose-dependent manner. FIG. 4 is a bar graph showing that viral infection is inhibited by interferon (100 IU/ml).

FIGS. 4,5,6 and 7 show the pan-genotypic HBV infection in iCell hepatocytes and are a series of bar graphs reflecting that induced pluripotent stem cell derived hepatocytes treated with the compound of example 1 are able to support robust infection of all four major HBV genotypes. Continuous presence of the compound of example 1 is required to maintain robust viral infection. Cells either were pre-treated with the compound of example 1 for 6 d before HBV infection (6d), or pre-treated for 6 days and during infection (throughout). Interferon (IFN) is used to show the specificity of HBV infection.

FIG. 8 is a bar graph showing that induced pluripotent stem cell derived hepatocytes treated with the compound of example 1 support infection of HBV isolated from patient sera (clinical isolates), and not from cell culture-derived virus (HepG2.2.15). iCell hepatocytes treated with the compound of example 1 support infection of patient-derived, but not cell culture-derived, HBV.

FIGS. 9,10,11 and 12 relate to HBV infectivity: serum vs. purified virus and are a series of bar graphs showing that removal of excess of HBsAg subviral particles (SVPs) present in serum is a prerequisite to achieve robust HBV infection in induced pluripotent stem cell derived hepatocytes treated with the compound of example 1. Cells were pre-treated with the compound of example 1 for 6 d before HBV infection (6d).

FIGS. 13 and 14 relate to the purification of HBV virus particles from excess HBsAg subviral particles (SVPs) and show that purified virus (Dane particles) were separated from HBsAg SVPs by Optiprep gradient ultracentrifugation. Viral markers (HBsAg and HBV DNA) and electron microscopy analysis were used to confirm that virus purification was successful.

FIG. 15-I is a microarray analysis (heat map-light photo) and FIG. 15-11 (dark photo) of induced pluripotent stem cell derived hepatocytes treated with the compound of example 1. Genes that were up- and down-regulated >2-fold (2 hr), >3-fold (24 hr), or >6-fold (7 day) post treatment are shown. The compound of example 1 down-regulated interferon-stimulated genes (ISGs) as early as 2 hr. Two genes (non-ISGs) that may also play roles in iCell hepatocyte susceptibility to HBV infection are shown: CREB3L1 (down-regulated as early as 2 hr post treatment) is shown to inhibit proliferation of infected cells by other viruses (HCV, WNV, and DNA viruses), and SLC10A1 (up-regulated at 7 day post-treatment) has been reported as an HBV receptor.

FIGS. 16-I and 16-H relate to the effect of the compound of example 1 on interferon-stimulated genes (ISGs) and provides pie charts (FIG. 17) showing the kinetic effect of the compound of example 1 on ISGs expression in induced pluripotent stem cell derived hepatocytes. A list of 975 interferon-stimulated genes (ISGs) are based on known ISGs in the public data database (see Table 1). 16-I and 16-H continue with each other.

FIG. 18 relates to the effect of compound of example 1 on ISG expression (975 genes) and provides pie charts showing examples of ISGs modulated by the compound of example 1 at 24 hr and 7 day post compound treatment. The list of 975 interferon-stimulated genes (ISGs) are based on known ISGs in the public data database (see Table 1).

Table 1 shows the kinetic effect of the compound of example 1 on ISGs at 2 hr, 24 hr, and 7 day post treatment (p-value <0.05).

TABLE 1 Raw Est Fold Unadjusted Gene_Symbol Change p-value 2 HOUR BUB1 −20.72 0.0012 RHOH −14.71 0.0068 CD80 −13.65 0.0032 SOCS3 −9.95 0.0002 JUNB −6.01 0.0009 JAK1 −5.55 0.0044 HLA-C −4.87 0.0002 ABCA9 −4.37 0.0101 SOCS1 −4.13 0.0086 C10orf10 −3.72 0.0119 MPO −3.18 0.0426 EPAS1 −2.61 0.0016 KAL1 −2.61 0.0382 ETV7 −2.54 0.0380 PCP4 −2.44 0.0402 TXNIP −2.04 0.0210 PHF11 −1.80 0.0134 FGF2 −1.76 0.0094 AKT3 −1.76 0.0495 EFNB2 −1.63 0.0194 BCL3 −1.44 0.0449 CEBPD −1.29 0.0413 GTPBP2 −1.29 0.0099 PIM3 −1.19 0.0328 ISGF3G −1.17 0.0152 EHHADH −1.16 0.0431 PCMT1 −1.10 0.0407 PI4K2B −1.08 0.0291 CSNK1D 1.10 0.0309 KPNB1 1.14 0.0136 PXK 1.17 0.0366 DRAP1 1.17 0.0269 GOLGA3 1.45 0.0117 SCARB2 1.50 0.0460 PHF15 1.74 0.0284 ASNS 1.80 0.0131 AES 2.07 0.0496 DDIT4 2.67 0.0061 ADAM19 2.77 0.0284 MAX 3.74 0.0081 CD300LF 5.42 0.0379 24 HOUR STEAP4 −65.16 0.0000 BUB1 −33.18 0.0010 SPTLC2 −10.08 0.0160 CD38 −10.02 0.0120 SOCS1 −9.88 0.0002 THBD −9.02 0.0349 NFE2 −8.28 0.0164 FFAR2 −7.50 0.0024 C4orf32 −7.20 0.0003 IFI16 −6.86 0.0024 AXL −6.82 0.0051 MT1X −6.73 0.0031 ICAM1 −6.60 0.0072 EMP1 −5.94 0.0498 GALNT2 −5.18 0.0036 CASP4 −5.09 0.0012 KIAA0040 −5.04 0.0004 JUNB −4.94 0.0005 RBL1 −4.92 0.0473 IL6 −4.57 0.0448 TMEM67 −4.34 0.0358 IL8 −4.32 0.0043 ETV7 −3.88 0.0149 IRF7 −3.86 0.0161 MAP3K8 −3.81 0.0009 HEG1 −3.64 0.0194 MYT1 −3.59 0.0432 SOCS3 −3.51 0.0069 MT1M −3.35 0.0130 PLSCR1 −3.34 0.0013 AMPH −3.29 0.0047 CREB3L3 −3.22 0.0206 BCL3 −3.11 0.0022 IFITM1 −3.11 0.0438 GBP4 −3.07 0.0095 ATF3 −3.06 0.0017 CASP5 −3.00 0.0268 EGR1 −2.86 0.0009 EPAS1 −2.84 0.0010 NPAS2 −2.77 0.0069 C10orf10 −2.71 0.0047 CYP1B1 −2.71 0.0070 IER3 −2.60 0.0003 CEBPD −2.58 0.0022 PIM3 −2.56 0.0014 GK −2.50 0.0089 IFNGR1 −2.46 0.0016 PNRC1 −2.42 0.0051 CSDA −2.38 0.0154 TEAD4 −2.33 0.0021 RAB27A −2.33 0.0001 MTHFD2L −2.20 0.0231 LRP4 −2.17 0.0255 STAT1 −2.14 0.0142 HLA-DPB1 −2.11 0.0189 LRG1 −2.10 0.0426 HLA-DPA1 −2.10 0.0476 MAFF −2.09 0.0007 TMEM49 −2.07 0.0189 MSR1 −2.06 0.0383 IGHM −2.00 0.0224 SQLE −1.98 0.0067 USP12 −1.96 0.0259 ITGA2 −1.94 0.0317 IFITM2 −1.90 0.0037 FKBP1B −1.90 0.0464 FUT4 −1.89 0.0458 HK2 −1.88 0.0001 B4GALT5 −1.87 0.0040 SERPINB9 −1.86 0.0057 PSMB9 −1.86 0.0115 PDGFRL −1.86 0.0367 PCTK2 −1.85 0.0318 ZNF295 −1.84 0.0001 GBP2 −1.83 0.0027 CCND3 −1.81 0.0045 ADM −1.81 0.0034 IMPA2 −1.80 0.0047 MLKL −1.78 0.0219 FLT1 −1.75 0.0454 ETS2 −1.73 0.0077 ARHGDIB −1.72 0.0228 BST2 −1.70 0.0187 ISG20 −1.70 0.0013 IQGAP1 −1.70 0.0260 FNDC3B −1.67 0.0005 SFTPC −1.66 0.0118 CYBA −1.64 0.0030 C1S −1.62 0.0023 TAP1 −1.60 0.0330 FNDC4 −1.59 0.0020 SLC15A2 −1.58 0.0023 SAT −1.57 0.0047 IFI27 −1.56 0.0314 DDX17 −1.56 0.0039 TAP2 −1.54 0.0062 FAM125B −1.54 0.0143 SLC25A28 −1.54 0.0079 CD47 −1.52 0.0133 FUBP1 −1.50 0.0293 PPP1R3D −1.49 0.0041 PDK1 −1.48 0.0461 NUB1 −1.47 0.0435 HIF1A −1.47 0.0019 EFNB2 −1.46 0.0052 SQRDL −1.45 0.0377 THBS1 −1.44 0.0100 ABHD5 −1.43 0.0363 UBE2S −1.40 0.0442 N4BP1 −1.40 0.0219 SFPQ −1.39 0.0284 FKBP5 −1.39 0.0035 TFPI −1.38 0.0032 NFKBIA −1.38 0.0066 RBMS1 −1.38 0.0010 ISGF3G −1.37 0.0466 ETV6 −1.37 0.0216 TXNIP −1.37 0.0419 IFITM3 −1.36 0.0154 TMEM2 −1.35 0.0179 ARHGEF3 −1.32 0.0088 TCF7L2 −1.29 0.0063 JAK2 −1.29 0.0208 CTSL −1.28 0.0165 CLCN6 −1.26 0.0351 BLZF1 −1.26 0.0017 IL6ST −1.25 0.0094 GTPBP1 −1.24 0.0002 ALCAM −1.24 0.0257 GOLGA3 −1.24 0.0019 PPIC −1.23 0.0273 USP25 −1.22 0.0497 PLOD2 −1.22 0.0161 CHST12 −1.21 0.0233 PSCD1 −1.21 0.0004 KDELR2 −1.19 0.0006 SMAD3 −1.19 0.0344 JAK1 −1.17 0.0411 ZNF24 −1.16 0.0411 BTG1 −1.16 0.0471 MCL1 −1.16 0.0127 MTMR1 −1.14 0.0117 KPNB1 −1.12 0.0098 YWHAE −1.11 0.0421 PCMT1 −1.10 0.0351 RANBP1 1.13 0.0297 GLUL 1.13 0.0013 MYD88 1.15 0.0364 CHD6 1.16 0.0032 GCH1 1.17 0.0189 VAT1 1.21 0.0142 PDGFA 1.23 0.0495 PTEN 1.23 0.0253 BAG1 1.26 0.0044 IRF3 1.26 0.0349 PSMA2 1.27 0.0148 IL28RA 1.28 0.0266 GTF2F1 1.28 0.0237 PEX26 1.29 0.0370 DRAP1 1.29 0.0011 ZFYVE26 1.31 0.0096 LIFR 1.33 0.0279 RBCK1 1.34 0.0199 DNAPTP6 1.34 0.0304 SSBP3 1.35 0.0121 TNFSF13B 1.36 0.0200 TRIM14 1.36 0.0030 TBX3 1.42 0.0070 GNAI1 1.43 0.0488 PCGF2 1.44 0.0148 RXRA 1.46 0.0187 SLC25A30 1.53 0.0499 TRIM26 1.56 0.0014 PCTK3 1.59 0.0160 CXCL10 1.71 0.0140 EHHADH 1.80 0.0196 IFIT3 1.88 0.0439 SDC2 1.96 0.0313 CRYM 2.03 0.0313 MAFB 2.60 0.0157 PADI2 2.66 0.0045 CX3CL1 2.73 0.0317 LEPR 2.89 0.0058 FBXO6 3.00 0.0042 AKAP12 3.33 0.0291 IFIT1 3.58 0.0062 C4orf33 3.95 0.0173 SOAT2 4.03 0.0043 G6PC 4.22 0.0001 RHOH 5.26 0.0270 BHMT 5.84 0.0082 DAY 7 STEAP4 −1275.83 0.0037 CRP −63.77 0.0011 CD38 −60.43 0.0007 CASP4 −43.41 0.0077 SOCS1 −42.96 0.0011 EREG −21.64 0.0383 AMPH −21.01 0.0152 SOCS3 −17.74 0.0017 IFITM1 −15.75 0.0016 CD300LF −15.50 0.0020 TIMP1 −11.92 0.0017 CASP5 −11.12 0.0299 IFI16 −11.00 0.0002 IER3 −9.69 0.0042 IL8 −9.22 0.0105 PHLDA1 −9.08 0.0062 ICAM1 −9.02 0.0003 JUNB −8.16 0.0001 CYR61 −7.93 0.0147 EFNB2 −7.87 0.0002 TXNIP −7.72 0.0042 MYC −7.27 0.0002 CEBPD −6.95 0.0000 THBD −6.70 0.0048 C10orf10 −6.70 0.0078 CYP1B1 −6.56 0.0033 TEAD4 −6.47 0.0013 GALNT2 −6.32 0.0059 MAP3K8 −6.22 0.0006 NFE2 −5.79 0.0110 CSDA −5.60 0.0046 ID1 −5.53 0.0022 ITGA2 −5.40 0.0038 AKT3 −5.29 0.0145 MTHFD2L −5.12 0.0053 RAB27A −5.10 0.0009 EGR1 −4.88 0.0050 HIF1A −4.78 0.0027 IFITM2 −4.71 0.0010 CREB3L3 −4.65 0.0011 GBP2 −4.50 0.0048 NPAS2 −4.43 0.0028 KIF5C −4.32 0.0252 CCND3 −4.18 0.0317 ULK4 −4.12 0.0349 HEG1 −4.07 0.0126 STAT1 −4.03 0.0004 CTGF −3.88 0.0200 MYT1 −3.88 0.0037 ADM −3.85 0.0014 IFNGR1 −3.76 0.0001 CD3D −3.72 0.0338 C4BPA −3.52 0.0129 AKR1B1 −3.52 0.0468 RBMS1 −3.48 0.0157 IRF7 −3.42 0.0007 ETV7 −3.42 0.0091 ARHGDIB −3.40 0.0073 NLRC5 −3.27 0.0271 HK2 −3.18 0.0001 PDGFRL −3.16 0.0005 BCL3 −3.15 0.0049 TMEM2 −3.07 0.0017 CFB −2.96 0.0419 LTBP2 −2.94 0.0244 HPSE −2.92 0.0055 LRP4 −2.80 0.0161 ARHGEF3 −2.76 0.0073 PHF11 −2.75 0.0010 BLVRA −2.70 0.0040 IKZF2 −2.69 0.0036 TNFSF14 −2.68 0.0089 HBE1 −2.67 0.0354 PIM3 −2.64 0.0002 C1R −2.64 0.0321 SPSB1 −2.63 0.0444 IQGAP1 −2.60 0.0069 PLSCR1 −2.59 0.0087 IL1RN −2.59 0.0490 PML −2.58 0.0290 PLAUR −2.56 0.0069 CD47 −2.51 0.0031 B4GALT5 −2.50 0.0019 FER1L3 −2.43 0.0270 HLA-DMA −2.39 0.0064 GK −2.38 0.0221 NEXN −2.35 0.0251 PPIC −2.26 0.0023 ATP10D −2.21 0.0020 ETS2 −2.17 0.0003 AHR −2.08 0.0469 ABHD5 −2.05 0.0003 EWSR1 −2.03 0.0011 FNDC3B −2.02 0.0010 TAP2 −2.02 0.0010 C1S −2.00 0.0143 TMEM49 −1.98 0.0047 UBE2S −1.95 0.0129 MAX −1.95 0.0013 SLFN12 −1.92 0.0054 CAPN2 −1.90 0.0461 STK39 −1.88 0.0183 FAM102A −1.88 0.0192 ETV6 −1.87 0.0008 SERPINB9 −1.86 0.0373 IRF8 −1.86 0.0014 EPAS1 −1.83 0.0015 IL6ST −1.83 0.0003 TFPI −1.80 0.0062 B2M −1.77 0.0444 KIAA0040 −1.76 0.0171 IFITM3 −1.73 0.0047 ATP1B3 −1.72 0.0096 TAP1 −1.72 0.0376 LYN −1.71 0.0031 SSR1 −1.71 0.0054 MAFK −1.70 0.0155 PHF15 −1.69 0.0002 RECQL −1.66 0.0266 IMPA2 −1.62 0.0124 NFIL3 −1.60 0.0293 CHST12 −1.59 0.0001 SFPQ −1.57 0.0026 ZC3HAV1 −1.57 0.0354 TCF7L2 −1.57 0.0205 SLC15A2 −1.52 0.0082 SAA1 −1.51 0.0118 WARS −1.50 0.0343 SPTLC2 −1.49 0.0401 HERC6 −1.49 0.0074 IL1R2 −1.48 0.0443 SLC25A28 −1.47 0.0437 CD164 −1.47 0.0227 ALCAM −1.46 0.0057 PCMT1 −1.45 0.0495 RIPK2 −1.45 0.0285 PTEN −1.44 0.0119 PUS1 −1.41 0.0014 TOR1B −1.39 0.0059 PON2 −1.39 0.0034 GNB1 −1.39 0.0211 FLT1 −1.38 0.0483 GRN −1.37 0.0031 HDAC2 −1.34 0.0170 KPNB1 −1.34 0.0001 MCL1 −1.33 0.0009 GLB1 −1.33 0.0347 RAN −1.29 0.0126 PXK −1.23 0.0286 FGG −1.22 0.0437 MTMR1 −1.20 0.0011 TARBP1 −1.18 0.0376 ZNF24 −1.16 0.0322 EIF2AK2 −1.14 0.0109 MYD88 1.19 0.0373 SF3A1 1.26 0.0281 TFDP2 1.26 0.0253 RXRA 1.28 0.0065 OPTN 1.28 0.0249 INPP5B 1.29 0.0440 C6orf85 1.31 0.0357 ZNF313 1.31 0.0011 XRCC6BP1 1.33 0.0068 BAG1 1.33 0.0124 PARP14 1.33 0.0439 NMI 1.34 0.0171 APOL6 1.36 0.0037 IRF1 1.36 0.0103 PEX26 1.38 0.0419 IL17RB 1.38 0.0313 JAK2 1.39 0.0180 CASP1 1.40 0.0364 PI4K2B 1.41 0.0128 SHMT2 1.44 0.0008 ZNF276 1.44 0.0257 BRF2 1.46 0.0432 IFIH1 1.47 0.0203 SSBP3 1.49 0.0092 CPT1A 1.49 0.0121 COL16A1 1.53 0.0188 ALDH1A1 1.54 0.0115 IL28RA 1.55 0.0243 MYOM2 1.59 0.0015 ASNS 1.63 0.0019 SCARB2 1.64 0.0454 UBE1L 1.65 0.0253 C4orf33 1.65 0.0090 SDC2 1.66 0.0134 TRIM14 1.68 0.0146 CREM 1.71 0.0115 TPM1 1.77 0.0064 SLC7A5 1.78 0.0089 ACSL1 1.78 0.0242 EIF2S2 1.81 0.0059 GCH1 1.83 0.0034 USP25 1.84 0.0201 TRIB3 1.84 0.0317 ITGA6 1.89 0.0133 SLC20A1 1.90 0.0164 PSMB10 1.91 0.0055 GPR171 1.93 0.0497 SRGAP2 1.95 0.0118 ISOC1 1.96 0.0400 NGFB 1.97 0.0265 CCL19 2.16 0.0359 PCTK3 2.27 0.0242 GBP3 2.28 0.0015 DHFR 2.31 0.0055 SAMD9L 2.42 0.0019 AGXT 2.54 0.0066 F3 2.54 0.0090 CLEC2D 2.54 0.0085 MT1F 2.56 0.0347 FCGR1A 2.56 0.0338 EMP1 2.60 0.0241 DNAPTP6 2.61 0.0167 SLC30A1 2.66 0.0129 IFIT3 2.91 0.0014 CKB 2.95 0.0079 HESX1 3.01 0.0169 RPL22 3.02 0.0043 CXCL11 3.15 0.0489 WAS 3.44 0.0054 GLUL 3.54 0.0002 CRYM 3.57 0.0035 HAO1 3.59 0.0350 FBXO6 3.59 0.0003 HLA-DOA 3.70 0.0240 IGHM 3.80 0.0153 SELL 3.83 0.0060 FAM70A 4.10 0.0037 PADI2 4.13 0.0004 CLEC4E 4.33 0.0139 CD163 4.54 0.0465 CD9 4.66 0.0392 PON1 5.18 0.0007 PLAC8 5.43 0.0070 RSAD2 5.52 0.0001 AXL 5.52 0.0299 SELP 5.95 0.0437 G6PC 6.12 0.0086 MAFB 6.31 0.0007 EHHADH 6.99 0.0047 TFEC 7.83 0.0320 PCK2 8.00 0.0043 CX3CR1 9.27 0.0030 SLC10A1 10.61 0.0012 SOAT2 11.97 0.0016 MSR1 16.00 0.0299 IFIT1 16.72 0.0004 UPP2 16.78 0.0093 BHMT 100.46 0.0000

Unless otherwise indicated, the following specific terms and phrases used in the description and claims are defined as follows:

The term “moiety” refers to an atom or group of chemically bonded atoms that is attached to another atom or molecule by one or more chemical bonds thereby forming part of a molecule. For example, the variables R¹-R¹¹ of formula I refer to moieties that are attached to the core structure of formula I by a covalent bond.

In reference to a particular moiety with one or more hydrogen atoms, the term “substituted” refers to the fact that at least one of the hydrogen atoms of that moiety is replaced by another substituent or moiety.

The term “optionally substituted” refers to the fact that one or more hydrogen atoms of a moiety (with one or more hydrogen atoms) can be, but does not necessarily have to be, substituted with another substituent.

The term “halogen” refers to a moiety of fluoro, chloro, bromo or iodo.

Unless otherwise indicated, the term “hydrogen” or “hydro” refers to the moiety of a hydrogen atom (—H) and not H₂.

The term in iCell hepatocytes refers to induced pluripotent stem cell derived hepatocytes from Cellular Dynamics International (CDI).

Unless otherwise indicated, the term “a compound of the formula” or “a compound of formula” or “compounds of the formula” or “compounds of formula” refers to any compound selected from the genus of compounds as defined by the formula (including any pharmaceutically acceptable salt or ester of any such compound).

The term “pharmaceutically acceptable salts” refers to those salts which retain the biological effectiveness and properties of the free bases or free acids, which are not biologically or otherwise undesirable. Salts may be formed with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid and the like, preferably hydrochloric acid, and organic acids such as acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, maleic acid, malonic acid, salicylic acid, succinic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, N-acetylcystein and the like. In addition, salts may be prepared by the addition of an inorganic base or an organic base to the free acid. Salts derived from an inorganic base include, but are not limited to, the sodium, potassium, lithium, ammonium, calcium, and magnesium salts and the like. Salts derived from organic bases include, but are not limited to salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines and basic ion exchange resins, such as isopropylamine, trimethylamine, diethylamine, triethylamine, tripropylamine, ethanolamine, lysine, arginine, N-ethylpiperidine, piperidine, polyamine resins and the like.

The compounds of the present invention can be present in the form of pharmaceutically acceptable salts. The compounds of the present invention can also be present in the form of pharmaceutically acceptable esters (i.e., the methyl and ethyl esters of the acids of formula I). The compounds of the present invention can also be solvated, i.e. hydrated. The solvation can be effected in the course of the manufacturing process or can take place i.e. as a consequence of hygroscopic properties of an initially anhydrous compound of formula I (hydration).

Compounds that have the same molecular formula but differ in the nature or sequence of bonding of their atoms or the arrangement of their atoms in space are termed “isomers.” Isomers that differ in the arrangement of their atoms in space are termed “stereoisomers.” Diastereomers are stereoisomers with opposite configuration at one or more chiral centers which are not enantiomers. Stereoisomers bearing one or more asymmetric centers that are non-superimposable mirror images of each other are termed “enantiomers.” When a compound has an asymmetric center, for example, if a carbon atom is bonded to four different groups, a pair of enantiomers is possible. An enantiomer can be characterized by the absolute configuration of its asymmetric center or centers and is described by the R- and S-sequencing rules of Cahn, Ingold and Prelog, or by the manner in which the molecule rotates the plane of polarized light and designated as dextrorotatory or levorotatory (i.e., as (+) or (−)-isomers respectively). A chiral compound can exist as either individual enantiomer or as a mixture thereof. A mixture containing equal proportions of the enantiomers is called a “racemic mixture”.

The term “a therapeutically effective amount” of a compound means an amount of compound that is effective to prevent, alleviate or ameliorate symptoms of disease or prolong the survival of the subject being treated. Determination of a therapeutically effective amount is within the skill in the art. The therapeutically effective amount or dosage of a compound according to this invention can vary within wide limits and may be determined in a manner known in the art. Such dosage will be adjusted to the individual requirements in each particular case including the specific compound(s) being administered, the route of administration, the condition being treated, as well as the patient being treated. In general, in the case of oral or parenteral administration to adult humans weighing approximately 70 Kg, a daily dosage of about 0.1 mg to about 5,000 mg, 1 mg to about 1,000 mg, or 1 mg to 100 mg may be appropriate, although the lower and upper limits may be exceeded when indicated. The daily dosage can be administered as a single dose or in divided doses, or for parenteral administration, it may be given as continuous infusion.

The term “pharmaceutically acceptable carrier” is intended to include any and all material compatible with pharmaceutical administration including solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, and other materials and compounds compatible with pharmaceutical administration. Except insofar as any conventional media or agent is incompatible with the active compound, use thereof in the compositions of the invention is contemplated. Supplementary active compounds can also be incorporated into the compositions.

In detail, the present invention relates to the compounds of formula I:

and pharmaceutically acceptable salts and esters thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are independently hydrogen or halogen; and R¹¹ is hydrogen or hydroxy. Unless indicated otherwise, the compounds within the genus of formula I encompass all possible stereoisomers (i.e., (R)-enantiomers, (S)-enantiomers) as well as racemic and scalemic mixtures thereof.

In one embodiment, R¹, R², R³, R⁴, and R⁵ are all hydrogen. In another embodiment, at least one of R¹, R², R³, R⁴, or R⁵ is halogen. In another embodiment, at least one of R¹, R², R³, R⁴, or R⁵ is fluoro. In another embodiment, R¹, R³, and R⁵ are all hydrogen and one of R² or R⁴ is fluoro and the other is hydrogen.

In another particular embodiment, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are all hydrogen. In another embodiment, at least one of R⁶, R⁷, R⁸, R⁹, and R¹⁰ is halogen. In another embodiment, at least one of R⁶, R⁷, R⁸, R⁹, and R¹⁰ is chloro. In another embodiment, R⁶, R⁸, and R¹⁰ are all hydrogen and one of R⁷ or R⁹ is chloro and the other is hydrogen.

In one embodiment, R¹¹ is hydrogen. In a more specific embodiment one of R¹, R², R³, R⁴, or R⁵ is halogen (preferably fluoro) and the others hydrogen; and R⁶, R⁷, R⁸, R⁹, R¹⁰, and R¹¹ are hydrogen.

In another embodiment, R¹¹ is hydroxy. In a more specific embodiment one of R¹, R², R³, R⁴, or R⁵ is halogen (preferably fluoro) and the others hydrogen; R⁶, R⁷, R⁸, R⁹, and R¹⁰ are hydrogen, and R¹¹ is hydroxy.

In one embodiment, the present invention relates to the compounds of formula IA:

and pharmaceutically acceptable salts and esters thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are independently hydrogen or halogen; and R¹¹ is hydroxy.

In another embodiment, the present invention relates to the compounds of formula IB:

and pharmaceutically acceptable salts and esters thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are independently hydrogen or halogen; and R¹¹ is hydroxy.

In one embodiment, the present invention relates to a compound of the formula:

In another embodiment, the present invention relates to a compound of the formula:

In another embodiment, the present invention relates to a compound of the formula:

In another embodiment, the present invention relates to a compound of the formula:

In another embodiment, the present invention relates to a compound of the formula:

In another embodiment, the present invention relates to a compound of the formula:

In another embodiment, the present invention relates to a compound of the formula:

The starting materials and reagents used in preparing these compounds generally are either available from commercial suppliers, such as Aldrich Chemical Co., or are prepared by methods known to those skilled in the art. The following synthetic reaction schemes are merely illustrative of some methods by which the compounds of the present invention can be synthesized, and various modifications to these synthetic reaction schemes can be made and will be suggested to one skilled in the art. Further exemplification can be found in the specific examples.

The compounds of the present invention can be prepared by any conventional means. Suitable processes for synthesizing these compounds are provided in the examples. Generally, compounds of formula I can be prepared according to the schemes illustrated below.

Starting with the methyl diaminobenzoate 2, which can be commercially available or prepared from the reduction of the nitro compound 1 with hydrogen and paladium on carbon, can be condensed with the pyridine aldehyde 3 and subsequently oxidized in situ with iodine to produce the benzoimidazole 4. The 2-methoxy-3-iodo-pyridine moiety of the benzoimidazole can be converted to the 3-chloro-pyrmidone 5 with 4 M hydrochloric acid in dioxane and heating to 100° C. for several hours. The aryl chloride of compound 5 can be displaced with 2-phenyl-ethylamines through nucleophilic aromatic substitutions with a base like triethylamine or N-methylmorpholine in a polar solvent like acetonitrile or N,N-dimethylformamide and heat for several hours. The resulting compound can be de-esterified using standard methods like lithium hydroxide in tetrahydrofuran and water and mild heat to yield the benzoimidazole carboxyl acid 6. The final compounds like 7 can be prepared by condensation of the acid 6 and with benzyl amines through standard amide coupling conditions like N,N-diisopropyl-ethylamine, and O-(7-azabenzotriazol-1-yl)-N,N,N′,N-tetramethyluronium hexafluorophosphate in a polar solvent like dimethylformamide (DMF).

EXAMPLES

Although certain exemplary embodiments are depicted and described herein, the compounds of the present invention can be prepared using appropriate starting materials according to the methods described generally herein and/or by methods available to one of ordinary skill in the art.

Example 1 Synthesis of 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide 2-(4-Iodo-2-methoxy-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid Methyl ester

In a 250 mL round-bottomed flask, methyl 2,3-diaminobenzoate (1.5 g, 9.03 mmol) was combined with methanol (25 mL) to give a yellow solution that was stirred under nitrogen and cooled in a water/dry ice bath. To this was added drop wise 4-iodo-2-methoxynicotinaldehyde (2.37 g, 9.03 mmol) dissolved in methanol (15 mL) and DMF (10 mL). During the addition more methanol (25.0 mL) was added to the reaction. The reaction was kept in the water/dry ice bath for 2.5 hr, allowed to warm to room temperature over 3 hr, and then cooled in a water/dry ice bath. To this was added drop wise iodine (1.49 g, 5.87 mmol) dissolved in methanol (15 mL) and then the reaction was allowed to warm to room temperature overnight. The reaction was concentrated, diluted with ethyl acetate (200 mL) and saturated Na₂S₂O₃ (200 mL) and mixed. Significant insoluble material was present and the mixture was filtered. The resulting solid was washed with ethyl acetate and water. The filtrate was separated and the resulting aqueous layer was extracted with ethyl acetate (100 mL) and DCM (3×150 mL). The organic layers were washed with saturated Na₂S₂O₃ and brine, combined, dried over MgSO4, and concentrated as a red oil/solid. The insoluble solid from the original extract was washed with DCM (5×100 mL) and the filtrate was concentrated as a dark red/black solid. The liquid extracted crude and the solid extract crude were dissolved in minimal DCM, combined, and purified by flash chromatography (silica gel, 120 g, 0% to 60% ethyl acetate in hexanes) to give 2-(4-iodo-2-methoxy-pyridin-3-yl)-3-H-benzoimidazole-4-carboxylic acid methyl ester, as a purple solid, 0.73 g LC/MS calcd for C₁₅H₁₂IN₃O₃ (m/e) 409.0, obsd 410.0 (M+H); ¹H NMR (DMSO-d₆): 12.68 (s, 1H), 8.05 (d, J=5.5 Hz, 1H), 8.01 (d, J=8.0 Hz, 1H), 7.88-7.95 (m, 1H), 7.67 (d, J=5.3 Hz, 1H), 7.38 (t, J=7.9 Hz, 1H), 3.96 (s, 3H), 3.82 (s, 3H). The original insoluble solid remaining after being extracted with DCM was subsequently extracted with boiling methanol (5×20 ml). The methanol filtrate was concentrated and dried, yielding additional product (83% pure by LCMS), as the sodium salt (assumed) and as a dark purple solid, 0.57 g. The remaining original insoluble solid after the DCM and methanol extractions yielded additional product (90% pure by LCMS), as the sodium salt (assumed) and as a purple solid, 0.88 g. The combined yield was 59%.

2-(4-Chloro-2-oxo-1,2-dihydro-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid methyl ester

Two reactions were initially done in parallel and were combined prior to heating. (In a 200 mL round-bottomed flask 2-(4-iodo-2-methoxy-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid methyl ester (solid isolated from liquid extraction) (0.88 g, 2.15 mmol) was combined with 1,4-dioxane (3 mL) to give a black suspension, 4 M HCl in 1,4-dioxane (14.5 mL, 58.1 mmol) was added portion wise, and mixture was stirred at room temperature, 17 hr. In a 200 mL round-bottomed flask, methyl 2-(4-iodo-2-methoxy-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid methyl ester (isolated from flash chromatography) (0.73 g, 1.78 mmol) was combined with 1,4-dioxane (2 mL) to give a black suspension, 4 M HCl in 1,4-dioxane (12 mL, 48.2 mmol) was added, and the mixture was stirred at room temperature, 17 hr.) The separate reactions were combined with addition of 1,4-dioxane (for rinsing) and 4 M HCl in 1,4-dioxane (20 mL). The reaction was heated in an oil bath at 100° C. for 3 hr and then allowed to cool to room temperature.

The reaction was filtered, and the solid was washed with 1,4-dioxane, water, 1,4-dioxane, hexanes, and dried over house vacuum yielding 2-(4-chloro-2-oxo-1,2-dihydro-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid methyl ester (0.91 g, 76.2% yield) as a black solid. LC/MS calcd for C₁₄H₁₀ClN₃O₃ (m/e) 303.0, obsd 304.1 (M+H); ¹H NMR (DMSO-d₆): 8.05-8.16 (m, 2H), 8.01 (d, J=7.3 Hz, 1H), 7.66-7.76 (m, 1H), 7.50 (t, J=7.9 Hz, 1H), 3.92-4.04 (m, 3H).

2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid methyl ester

In a 40 mL vial, 2-(4-chloro-2-oxo-1,2-dihydro-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid methyl ester (0.91 g, 3.00 mmol), (S)-2-amino-1-phenylethanol (822 mg, 5.99 mmol) and N-methylmorpholine (909 mg, 988 μL, 8.99 mmol) were combined with DMF (20 mL) to give a black suspension. The vial was sealed and heated in a dry block at 85° C. for 6.5 hr and allowed to cool to room temperature over the weekend. The reaction was diluted with water and the resulting precipitate was washed with water and hexanes yielding 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid methyl ester (0.87 g, 71.8% yield) as a light purple solid. LC/MS calcd for C₂₂H₂₀N₄O₄ (m/e) 404.0, obsd 405.2 (M+H); ¹H NMR (DMSO-d₆): 13.53 (s, 1H), 11.26 (d, J=5.8 Hz, 1H), 10.85 (t, J=5.1 Hz, 1H), 7.85 (d, J=8.0 Hz, 1H), 7.76-7.82 (m, 1H), 7.55 (d, J=7.3 Hz, 2H), 7.34-7.42 (m, 3H), 7.26-7.34 (m, 2H), 6.22 (d, J=7.5 Hz, 1H), 5.80 (d, J=4.5 Hz, 1H), 4.85-5.00 (m, 1H), 3.98 (s, 3H), 3.64-3.77 (m, 1H), 3.53-3.63 (m, 1H).

2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid

In a 200 mL round-bottomed flask, 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid methyl ester (0.87 g, 2.15 mmol) and LiOH (258 mg, 10.8 mmol) were combined with THF (20 mLl) and Water (5 mL) to give a purple suspension. The reaction was stirred at room temperature overnight. The next day the reaction was heated in dry block at 50° C. for 3.5 hr and cooled to room temperature. The reaction was dilute with water, concentrated, dilute with more water, and acidify with 1M HCl, and filtered. The resulting solid was washed with water and hexanes, and dried over house vacuum yielding 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid (0.86 g, 102% yield) as a purple solid. LC/MS calcd for C₂₁H₁₈N₄O₄ (m/e) 390.0, obsd 391.2 (M+H); ¹H NMR; (DMSO-d₆): 13.35 (s, 1H), 11.19 (d, J=6.0 Hz, 1H), 10.97 (t, J=4.9 Hz, 1H), 7.75 (dd, J=7.7, 3.9 Hz, 2H), 7.56 (d, J=7.3 Hz, 2H), 7.22-7.44 (m, 5H), 6.20 (d, J=7.5 Hz, 1H), 5.80 (br. s., 1H), 4.92 (t, J=5.5 Hz, 1H), 3.54-3.74 (m, 3H).

2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide

In a 100 mL round-bottomed flask, 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid (0.84 g, 2.15 mmol), 3-fluoro-benzylamine (296 mg, 270 μL, 2.37 mmol) and DIEA (612 mg, 827 μL, 4.73 mmol) were combined with DMF (10 mL) to give a black solution and to this was added HATU (982 mg, 2.58 mmol). The reaction was stirred at room temperature overnight. The next day, the reaction was dripped into water and the resulting precipitate was filtered and washed with water, ethyl ether, and hexanes. The purple solid was incompletely dissolved in minimal boiling ethanol and the resulting solid that formed upon cooling was filtered and washed with ethanol and hexanes yielding 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide as a light purple solid. LC/MS calcd for C₂₈H₂₄FN₅O₃ (m/e) 497.0, obsd 497.9 (M+H); ¹H NMR (DMSO-d₆-TFA): 11.25 (br. s., 1H), 10.77 (br. s., 1H), 9.32 (t, J=5.8 Hz, 1H), 7.71-7.97 (m, 2H), 7.14-7.63 (m, 10H), 7.03-7.13 (m, 1H), 6.21 (d, J=7.5 Hz, 1H), 4.84 (br. s., 1H), 4.68 (br. s., 2H), 3.65 (d, J=12.5 Hz, 1H), 3.46 (d, J=7.0 Hz, 1H).

Example 2 Synthesis of 2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid benzylamide

2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid benzylamide was synthesized from 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid, benzylamine, DIEA, HATU and DMF using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide yielding 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid benzylamide. LC/MS calcd for C₂₈H₂₅N₅O₃ (m/e) 479.0, obsd 480 (M+H). ¹H NMR (tautomers 1:2; DMSO-d₆): 13.38-13.52 (m, 1H), 11.14-11.38 (m, 1H), 10.33-11.02 (m, 1H), 9.18-9.43 (m, 1H), 7.69-7.99 (m, 2H), 7.15-7.61 (m, 12H), 6.12-6.30 (m, 1H), 5.74-5.99 (m, 1H), 4.52-4.96 (m, 3H), 3.49-3.30 (m, 2H).

Example 3

Synthesis of 2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 4-fluoro-benzylamide

2-[4-((S)-2-Hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid4-fluoro-benzylamide was synthesized from 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid, benzylamine, DIEA, HATU and DMF using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide yielding 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 4-fluoro-benzylamide. LC/MS calcd for C₂₈H₂₄FN₅O₃ (m/e) 497.0, obsd 498 (M+H). ¹H NMR (DMSO-d₆): 13.35-13.53 (m, 1H), 11.13-11.38 (m, 1H), 10.35-11.03 (m, 1H), 9.19-9.42 (m, 1H), 7.68-7.97 (m, 2H), 7.24-7.58 (m, 9H), 7.08-7.22 (m, 2H), 6.13-6.30 (m, 1H), 5.74-6.02 (m, 1H), 4.49-4.98 (m, 3H), 3.49-3.29 (m, 2H).

Example 4 Synthesis of 2-{4-[2-(3-Chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid Benzylamide

2-{4-[2-(3-Chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid methyl ester was synthesized from 2-(4-chloro-2-oxo-1,2-dihydro-pyridin-3-yl)-3H-benzoimidazole-4-carboxylic acid methyl ester, 2-(3-Chloro-phenyl)-ethylamine, triethylamine, and ACN using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid methyl ester yielding 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid methyl ester.

2-{4-[2-(3-Chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid was synthesized from 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid methyl ester, LiOH, THF, and water using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid yielding 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid.

2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid benzylamide was synthesized from 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid, benzylamine, DIEA, HATU and DMF using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide yielding 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid benzylamide. LC/MS calcd for C₂₈H₂₄ClN₅O₂ (m/e) 497.0, obsd 498 (M+H).

Example 5 2-{4-[2-(3-Chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 4-fluoro-benzylamide

2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 4-fluoro-benzylamide was synthesized from 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid, benzylamine, DIEA, HATU and DMF using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide yielding 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 4-fluoro-benzylamide. LC/MS calcd for C₂₈H₂₃ClFN₅O₂ (m/e) 515.0, obsd 516 (M+H). ¹H NMR (tautomers, DMSO-d₆): 13.30-13.51 (m, 1H), 11.11-11.49 (m, 1H), 9.98-10.95 (m, 1H), 9.06-9.36 (m, 1H), 7.68-8.00 (m, 2H), 6.93-7.65 (m, 11H), 6.22 (d, J=7.3 Hz, 1H), 4.47-4.74 (m, 2H), 3.59-3.85 (m, 2H), 3.05 (t, J=6.9 Hz, 2H).

Example 6 Synthesis of 2-{4-[2-(3-Chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide

2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide was synthesized from 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid, benzylamine, DIEA, HATU and DMF using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide yielding 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-3-carboxylic acid 4-fluoro-benzylamide. LC/MS calcd for C₂₈H₂₃ClFN₅O₂ (m/e) 515.0, obsd 516 (M+H). ¹H NMR (tautomers, DMSO-d₆): 13.42 (s, 1H), 11.15-11.46 (m, 1H), 10.00-10.91 (m, 1H), 9.08-9.41 (m, 1H), 7.69-8.00 (m, 2H), 6.98-7.59 (m, 11H), 6.22 (d, J=7.5 Hz, 1H), 4.49-4.78 (m, 2H), 3.63-3.82 (m, 2H), 3.05 (t, J=6.8 Hz, 2H).

Example 7 Synthesis of 2-{4-[2-(3-Chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 2-fluoro-benzylamide

2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 2-fluoro-benzylamide was synthesized from 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid, benzylamine, DIEA, HATU and DMF using a similar procedure as 2-[4-((S)-2-hydroxy-2-phenyl-ethylamino)-2-oxo-1,2-dihydro-pyridin-3-yl]-3H-benzoimidazole-4-carboxylic acid 3-fluoro-benzylamide yielding 2-{4-[2-(3-chloro-phenyl)-ethylamino]-2-oxo-1,2-dihydro-pyridin-3-yl}-3H-benzoimidazole-4-carboxylic acid 2-fluoro-benzylamide. LC/MS calcd for C₂₈H₂₃ClFN₅O₂ (m/e) 515.0, obsd 516 (M+H). ¹H NMR (tautomers, DMSO-d₆): 13.33-13.49 (m, 1H), 11.14-11.45 (m, 1H), 10.05-10.92 (m, 1H), 9.08-9.32 (m, 1H), 7.70-7.98 (m, 2H), 7.02-7.61 (m, 11H), 6.16-6.32 (m, 1H), 4.53-4.80 (m, 2H), 3.43-3.84 (m, 2H), 2.75-3.12 (m, 2H).

The compounds of formula I possess valuable properties. It has been found that said compounds are useful in differentiating stem cells into more mature or adult-like hepatocytes for more accurate pharmaceutical testing and research. The activity of the present compounds in differentiating stem cells into more mature or adult-like hepatocytes is demonstrated by the following assays. In addition, the effect of the compounds of the present invention on host genes that led to cell susceptibility to HBV are also described.

In Vitro Testing with Human Induced Pluripotent Stem Cells

Human iPSC-derived hepatocytes (iCell® Hepatocytes) were exposed to the compounds of formula I with the goal of identifying conditions that favor greater functionality that better models the adult organ. High-throughput, microfluidic quantitative RT-PCR (qRT-PCR) was used to examine the expression of 32 genes that span a spectrum of hepatocyte functions that were either low or exhibited an immature phenotype in hiPSC-derived hepatocytes when compared to adult primary human hepatocytes. During the primary screen, multiple compounds were identified that resulted in a significant increase in a number of maturation-associated genes. Gene expression changes were validated and confirmed in a secondary screen, and functional consequences were queried.

Cells and Culture Conditions

Fresh iCell® Hepatocytes (day 20-23) were plated and cultured according to iCell Hepatocytes Dissociation and Plating User's Guide at 60 k cells per well in 96 well BIO Collagen IV coated plates (BD Cat#354429) 4 Hours post plating Medium C was removed and replaced with a 1:50 Matrigel (Cat#354227) overlay in Medium D. We dosed the cells at 5 uM in Medium D and 1% DMSO 24 hours post plating. Day 3, media was removed and we dosed again at 5 uM. Day 4 we Harvested RNA.

Gene Expression Profiling

Sample RNA was isolated using TaqMan® Gene Expression Cells-to-CT™ Kit (Life Technologies Cat#4387299) froze at −80 C at various time points post compound treatment. All samples were processed by microfluidic quantitative PCR using the Biomark Fluidigm 96.96 chips (BMK-M-96.96) and ABI Taqman probes. Normalization and model-based expression measurements were calculated using the Biogazelle qBASE and Genorm software. All sample data are the average of triplicates and normalized to 5 housekeeping genes for a relative gene expression value. Expression values are calculated by the fold change over vehicle control. See FIGS. 1 and 2.

Top compound hits were chosen based on a compound's ability to alter the gene expression in a manner predicted to increase cellular maturity, for instance an increase of adult specific markers or a decrease in fetal specific markers. For the secondary confirmation screen compound hits were chosen for a dose response on a broader panel of genes. We discovered that the compound of Example 1 caused the global increase of genes spanning hepatocyte function at multiple doses. (FIG. 1). Exposure to the compound of example 1 and five other structural analogs (Examples 2-7) results in the similar phenotypic change in iCell Hepatocytes based on gene expression of a panel of maturation-associated genes. (FIG. 2). The results in using the compound of Example 1 exhibited reproducible gene expression changes on 5+ independent batches of iCell Hepatocytes and is being further studied with the goal of identifying the mechanisms of action and functional consequences. Upon treatment with the compound of Example 1, iCell Hepatocytes are able to be infected in multiple genotypes of HBV and generate robust numbers of infected hepatocytes based on IHC and ELISA.

Microarray Analysis

iCell Hepatocytes treated with the compound of example 1 results in the up and down-regulation of a host of genes; including a kinetic effect on interferon-stimulated gene (ISGs) expression. See FIGS. 15-I and 15-H, 16-I and 16-H and 18 and Table 1.

Purification of HBV from Serum

Two hundred microliters of HBV-containing serum was applied onto a 10-50% Optiprep gradient in SW41 tubes. Samples were centrifuged at 100,000×g for 2 hr at 4 C. Five hundred microliters fractions were collected from the top; each fraction was analyzed for HBsAg (ELISA) and HBV DNA (TaqMan PCR). Fractions containing virus were stored at −80 C. See FIGS. 13 and 14.

Infection of iCell Hepatocytes with HBV

Fresh iCell® Hepatocytes (day 20-23) were plated and cultured according to iCell Hepatocytes Dissociation and Plating User's Guide at 60 k cells per well in 96 well BIO Collagen IV coated plates (BD Cat#354429) 4 Hours post plating Medium C was removed and replaced with a 1:50 Matrigel (Cat#354227) overlay in Medium D. Twenty four hours post plating, cells were treated with 1 uM of the compound of example 1 in Medium D containing 1% DMSO. Media containing fresh compound was replenished 2 days later. At day 4 post plating, cells were infected with HBV at MOI (multiplicity of infection) of 10. Briefly, purified virus was diluted in medium D containing the compound of example 1 and incubated with cells for 4-6 hr or overnight. After removal of virus inoculum, fresh media containing 1 uM of the compound of example 1 was added and cells were incubated for 14 days with a medium change every 2 days. Culture media were analyzed for secreted viral antigens (HBsAg, HBeAg) and HBV DNA. See FIGS. 3, 4, 5 and 6.

Taken together, the data shows that using the compounds of formula I as endogenous signals provides a rapid, efficient, nongenetic and cost-effective means to modulate iCell Hepatocyte functionality. The generation of iCell Hepatocytes infected with HBV using the compounds of formula I provides a method for basic virology and drug discovery. Small molecule library screens for the functional improvement of stem cell derived cells may lead to a new generation of in vitro assays for drug discovery. 

We claim:
 1. A compound of formula I:

or a pharmaceutically acceptable salt or ester thereof; wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are independently hydrogen or halogen; and R¹¹ is hydrogen or hydroxy.
 2. A compound of claim 1 wherein R¹, R², R³, R⁴, and R⁵ are all hydrogen.
 3. A compound of claim 1 wherein at least one of R¹, R², R³, R⁴, or R⁵ is halogen.
 4. A compound of claim 1 wherein at least one of R¹, R², R³, R⁴, or R⁵ is fluoro.
 5. A compound of claim 1 wherein R¹, R³, and R⁵ are all hydrogen and one of R² or R⁴ is fluoro and the other is hydrogen.
 6. A compound of claim 1 wherein R⁶, R⁷, R⁸, R⁹, and R¹⁰ are all hydrogen.
 7. A compound of claim 1 wherein at least one of R⁶, R⁷, R⁸, R⁹, and R¹⁰ is halogen.
 8. A compound of claim 1 wherein at least one of R⁶, R⁷, R⁸, R⁹, and R¹⁰ is chloro.
 9. A compound of claim 1 wherein R⁶, R⁸, and R¹⁰ are all hydrogen and one of R⁷ or R⁹ is chloro and the other is hydrogen.
 10. A compound of claim 1 wherein R¹¹ is hydrogen.
 11. A compound of claim 1 wherein one of R¹, R², R³, R⁴, or R⁵ is fluoro and the others hydrogen; and R⁶, R⁷, R⁸, R⁹, R¹⁰, and R¹¹ are hydrogen.
 12. A compound of claim 1 wherein R¹¹ is hydroxy.
 13. A compound of claim 1 wherein R¹, R², R³, R⁴, or R⁵ is fluoro and the others hydrogen; R⁶, R⁷, R⁸, R⁹, and R¹⁰ are hydrogen, and R¹¹ is hydroxy.
 14. A compound of claim 1 which is a compound of the formula:


15. A compound of claim 1 which is a compound of the formula:


16. A compound of claim 1 which is a compound of the formula:


17. A compound of claim 1 which is a compound of the formula:


18. A compound of claim 1 which is a compound of the formula:


19. A compound of claim 1 which is a compound of the formula:


20. A compound of claim 1 which is a compound of the formula:


21. A compound of claim 1 which is a compound of formula IA:

and pharmaceutically acceptable salts and esters thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are independently hydrogen or halogen; and R¹¹ is hydrogen or hydroxy.
 22. A compound of claim 1 which is a compound of formula IB:

and pharmaceutically acceptable salts and esters thereof, wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, and R¹⁰ are independently hydrogen or halogen; and R¹¹ is hydrogen or hydroxy.
 23. A pharmaceutical composition comprising a compound of claim 1 and a pharmaceutically acceptable carrier.
 24. A method for differentiating stem cells into hepatocytes comprising administering to said stem cells a compound of claim
 1. 25. A method according to claim 24, wherein the hepatocytes are infected with Hepatitis B virus.
 26. A method according to claim 25, wherein the infected hepatocytes are used to screen compounds to treat Hepatitis B virus.
 27. A method according to claim 24, wherein interferon-stimulated genes are down regulated in differentiated hepatocytes.
 28. A method according to claim 27, wherein said hepatocytes are infected with Hepatitis B virus.
 29. A method according to claim 25, wherein the Hepatitis B virus is a patient-derived Hepatitis B virus and not a cell culture-derive Hepatitis B virus.
 30. A method according to claim 24, wherein the cells are infected with a substantially pure population of Dane particles. 